If you're looking to build wealth, traditional forms of investment aren't going to get you there — at least according to young, rich people.

Of those ages 21 to 43 with at least $3 million in investable assets, just 28% say it's possible to achieve above-average returns with stocks and bonds, according to the 2024 Bank of America Private Bank Study of Wealthy Americans.

Among those ages 44 and up, the inverse is true: 72% say classic investing practices work just fine. And 84% of the older generation views stocks — domestic and foreign — as presenting the greatest opportunity for investment growth on a long list of asset classes.

Of course, owning stocks has been a wealth builder for generations of Americans, with the broad U.S. stock market returning some 10% per year over the past century or so, assuming reinvested dividends.

For younger wealthy investors, though, stocks come in behind seven other types of investments, including real estate, cryptocurrency, private equity and direct investment into companies.

It turns out, even among the jet set, younger investors may have a thing or two to learn from their older counterparts, says Brad Klontz, a certified financial planner and professor of financial psychology at Creighton University.

"Essentially, the older ones have the more accurate list," he says. "All of the studies I've done show the older we get, the more healthy our beliefs are around money, because, frankly, we learn the hard way."

Klontz says that younger wealthy investors may be falling victim to some of the same cognitive biases that regular investors do — and it may be holding them back from maximizing their returns. Here's a look at their two key mistakes: ignoring conventional wisdom and prioritizing exclusivity.

Young people have ignored traditional advice 'for thousands of years'

In general, it's not surprising that younger investors, regardless of wealth level, want to chart a different path than older generations.

"The desire to push against conventional wisdom is a really important developmental stage," Klontz says. "Young people on social media tell me that [traditional investing advice] isn't the way it's done anymore. Everything's changed. This is something that people have been saying for thousands of years."

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Older investors tend to favor the returns offered by stocks, because that is what has historically delivered returns. Plus, many of them likely tried — and failed — to find a new, faster, better way to build wealth.

"If you asked me that question in my 20s, I might have said day trading — just before I lost all my money day trading," Klontz says.

It's a story Klontz sees echoed in younger investors' enthusiasm for cryptocurrency, which has offered eye-popping returns for some investors while crushing the portfolios of others who speculated on an extremely volatile asset.

"When it comes to some of the tried-and-true approaches to investing, it really is a long game," he says. "And when I hear people talk about crypto and alternative assets, that's much more of a short-game mindset. They're probably interested in making money faster."

'We're inherently obsessed with status'

Another commonality Klontz sees among young, rich Americans' favorite investments: exclusivity.

Real estate, private equity deals and direct investment into companies all require a level of cash that most individual investors don't have. If you want to buy an investment property you'll need enough for a down payment, for instance. And to buy in to a private equity fund, you'll have to be an accredited investor, generally meaning you have income over $200,000 or a net worth north of $1 million.

These investments must be better than the stuff everyone can buy, the thinking goes, because otherwise it wouldn't be so tough to invest. However, that's not necessarily true.

For just a few bucks and a minuscule fee, you can buy exposure to the S&P 500 — a measure of the broad U.S. stock market — in the form of an exchange-traded fund.

In doing so, you'd buy into an index that over the past three decades has trounced the U.S. residential real estate market. You'll be buying something that comes with much less risk than investing in a small business, half of which fail in their first five years, according to the Bureau of Labor Statistics.

And while data is mixed on whether private equity funds tend to outperform public stocks over the long term, you'll generally have to pay an exorbitant fee for the privilege of investing in one — often 1.5% to 2% of your invested assets per year, plus 20% of your annual profits over a certain threshold. It's an especially risky move given the extent to which investment fees eat into long-term returns.

None of which is to say that any investment in real estate, private equity or a small business is bound to fail or even underperform the broad stock market. But it's important to acknowledge your reasons for favoring one investment over another, says Klontz.

"We're all inherently obsessed with our status," he says. "Denying it just tells me that you're psychologically immature."

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